advice?

Gorilla girl xl and blue dream. only watering when nearly dry without pH balanced water and using foxfarm medium. I’m a bit nervous about the darker leaves, over watering or deficiency in Nitrogen? I also want to begin nutrient use in a few days, should I get liquid nutrients for my water or dry nutrition for the soil? been keeping temp between 70-80 F with 25-45% humidity.

Looks fine to me. TBH you really couldn't ask for better looking plants using FF without pH'ing water.

Nice job so far

For the next week let the babies dry back with water only. Sprinkle some worm castings after a week and or up pot into a 1 gallon which will have more feed. Less is better right now. When you water you don’t have to saturate the soil dense with water. A mediocre soaking will achieve a better dry back from 1-2 days vs 3-4 days. In a week the roots will be more filled and you can water more. Using a seedling mat can promote root growth and faster dry backs especially in solo cups.
They’re looking good.
For 1gallon containers and smaller I like to use 2-2-2 Dr earth once they’re starting to get hungry.

Fill up your cups.

Fox Farm is nute dense - some initial symptoms will show but plant will acclimate ( as long as you do not do something crazy ) …. Carry on.

Up the humidity. Put them in big enough pots and use something like 4-4-4 Gaia Green or just top dress with more Ocean Forest. Dark green wouldn’t be a deficiency of N.

Also there’s a spot on the top left plant. Located on its largest leaf on the right, is that from a critter?